Apparatus for reception and discharge of liquid metal

ABSTRACT

A heating means and a feed container having a feed cavity therein are both coupled to a container which is adapted to receive and discharge liquid metal. The reception and discharge container includes a valve operated opening for selectively pouring out the liquid metal. A feed channel is provided between the lower end portions of the feed cavity and the container cavity such that liquid metal poured into the feed cavity flows into the container cavity through the feed channel. The feed container has a wall the height of which is equal to the maximum level of liquid metal in the container cavity such that when the liquid metal reaches the desired maximum level, the excess liquid metal is poured off over the wall.

United States Patent Buhrer et al.

APPARATUS FOR RECEPTION AND DISCHARGE OF LIQUID METAL Inventors: ErwinBuhrer, Schaffhausen, Switzerland; Anton Alt, Metzkausen, GermanyAssignee: Georg Fischer Aktiengesellschaft,

Schaffhausen, Switzerland Filed: Nov. 16, 1970 Appl. No.: 89,778

Foreign Application Priority Data Nov. 18, 1969 Switzerland ..l7l3l/69References Cited Tagiaferri 4.13/29 2,427,817 9/1947 Tama ..l3/291,796,871 3/1931 Madorsky ..266/37 UX 2,586,596 2/1952 Bahney 13/292,892,878 6/1959 Tostmann. l3/29 3,005,858 10/1961 Lang ..l3/29 PrimaryExaminerJ. Spencer Overholser Assistant Examiner-John S. BrownAttorney-Flynn & Frishauf [57] ABSTRACT A heating means and a feedcontainer having a feed cavity therein are both coupled to a containerwhich is adapted to receive and discharge liquid metal. The receptionand discharge container includes a valve operated opening forselectively pouring out the liquid metal. A feed channel is providedbetween the lower end portions of the feed cavity and the containercavity such that liquid metal poured into the feed cavity flows into thecontainer cavity through the feed channel. The feed container has a wallthe height of which is equal to the maximum level of liquid metal in thecontainer cavity such that when the liquid metal reaches the desiredmaximum level, the excess liquid metal is poured off over the wall.

13 Claims, 4 Drawing Figures PATENTEUmzomn SHEET 10F a PATENTEUHARZOIEJHSHEET 30F 3 Fig. 4

APPARATUS FOR RECEPTION AND DISCHARGE OF LIQUID METAL The presentinvention relates to an improved apparatus having a container for thereception and discharge of liquid metal which is equipped with a devicefor heating the liquid metal and a stopper mechanism at the pouringoutlet, and more particularly to such an apparatus having an improvedfilling arrangement.

Molding and casting equipment is known in which the pouring apparatus isprovided with a container for reception and discharge of liquid metal,the container having on its underside a pouring outlet which can beclosed with a stopper. These containers also include filling ports forthe liquid metal. There are also known types in which, instead of havingfilling ports, the curved top of the container may be lifted and tiltedfor filling.

In molding and casting installations it is unavoidable thatinterruptions of operation take place. These interruptions may be causedby regular work breaks, by operational breakdowns, change of mold, etc.If for example a liquid metal is poured out, as in the case of sphericalgraphite'iron containing traces of magnesium, the resulting materialwill be spherical graphite iron only if the residual magnesium contentis retained over a long period of time. This is not possible withpresently known apparatus. In the known apparatus, one an operationalinterruption exceeds minutes, it is necessary to repeat the magnesiumtreatment because the residual magnesium content is no longer of thenecessary magnitude.

It has further been observed that a decrease in quality may occur,especially during operational interruptions, in case the molten metalscontain constituents that easily react with atmospheric air or slag.

Furthermore, the indispensable slagging-off operation for the removal ofslag that forms or is introduced with the liquid metal constitutes workthat, when presently known containers are utilized, is alwaysdisagreeable and entails high heat loss.

Experience has further shown that reactions between the slag and thefurnace lining reduces the durability of the furnace lining. Theseundesirable reactions become more pronounced as the temperature of theliquid metal in the container rises.

It is the object of the present invention to eliminate thesedisadvantages of the prior art apparatus.

SUMMARY OF THE INVENTION The apparatus for the reception and dischargeof liquid metal includes a container, a heating device, and

a feed container alongside the heating device. A feed passage isprovided at the lower portions of the container cavity and of the feedcavity for flow of liquid metal to the container.

The above and other objects and features of the present invention willbecome apparent from the following detailed description taken inconjunction with the accompanying drawings, in which:

FIG. 1 is a cross section of the container and feed arrangement of thepresent invention taken along line I I of FIG. 3;

FIG. 2 is a cross section of the container and of the heating unit ofthe present invention taken along line II-II of FIG. 3;

FIG. 3 is a top view of the container; and

FIG. 4 is a section of the feed opening taken along line IVIV of FIG. 3.

FIG. 1 illustrates a preferred embodiment of the present invention. Acontainer 1 having a cavity 7 therein is detachably connected with afeed container 2 by means of a joint 5. Joint 5 is not further describedherein. Its design should be apparent to those skilled in the art. Thefeed container 2 has a feed cavity 3 formed therein and has at its upperend a pouring-in opening 6. Feed container 2 is at its lower endconnected with the container cavity 7 by means of an inclined feedpassage or channel 4. The angle of inclination a of feed channel 4 ispreferably approximately equal to the angle of inclination B of theheating channel 12 illustrated in FIG. 2. By virtue of this arrangement,an equal level is reached in feed cavity 3 and in heating channel 12when the container cavity 7 is emptied. On the upper side of container 1a valve device 8 is provided, which comprises a hermetically closing cap9 and a slide valve member 10.

Maximal fill level 18 of the liquid metal in container cavity 7 is thesame level as rim 19 (see FIG. 4) of pouring opening 6 of feed container2.

FIG. 2 illustrates the container 1, which is detachably connected with aheating unit 11. Heating unit 1 1 comprises a heating channel 12, whichis directly connected with container cavity 7, also at the lower portionof cavity 7. A stopper bar 13 (already known per se) is mounted incontainer 1 and cooperates with the valve seat 14, as is well known. Aseal 15 for the stopper bar 13 is provided in the curved upper wall ofcontainer 1 where the stopper bar 13 enters the container 1 to seal outthe ambient atmosphere from container cavity 7. An opening 20 isprovided to permit connection with a vacuum pump (not shown in thedrawings) or connection with a gas intake (also not shown in thedrawings).

FIG. 3 illustrates a top view of the arrangement of container 1 withfeed container 2 and heating unit 11. Feed container 2 and heating unit11 are arranged on the same side of container 1, so that when shuttingthe apparatus down, it is possible to simultaneously empty heatingchannel 12 and the feed channel 4 by tilting the container 1.

FIG. 4 illustrates a sectional view of feed container 2 taken along lineIVIV of FIG. 3, showing the feed opening 6, feed cavity 3, feed channel4, rim 19 and slag overflow 17.

The mode of operation of the apparatus of the present invention will nowbe described. Liquid metal is introduced into the container 1 throughthe feed opening 6 until the liquid metal rises to the level of the rim19 (FIG. 4) of feed opening 6. This level is the same as the desirablemaximal fill level 18 (FIG. 1) of the liquid metal within the containercavity 7. By virtue of the fact that feed container 2 is formed with afeed cavity 3, the slag contained in the liquid metal does not reachcontainer cavity 7, but flows'off over the rim 19 of the feed opening 6after the container 1 is filled to the level 18. The result is that noslag gets into container cavity 7. Thus, it is possible to introduceadditives or alloying elements into the liquid metal contained in thecontainer cavity 7 by way of the valve 8 which is installed in the wallof container 1. The additives or alloying elements may display a lowerspecific gravity than the liquid metal when the present invention isused. A suction pump may be fitted over opening 20 so as to create apressure (negative) in container cavity 7. However, it is also possibleto introduce through opening 20 an inert gas or other gaseous agent, soas to prevent an alteration of the liquid metal inside the containerand/or to induce and/or control the liquid metal and its reactions insome specific way.

Thus, the arrangements of feed cavity 3, container cavity 7 and lowerfeed channel 4 provides a self-leveling system whereby the liquid levelin the feed cavity 3 and container cavity 7 seek the same level. This issimilar to an inverted siphon arrangement.

The desired temperature of the liquid metal in container l is maintainedby the attached heating unit 11, which may also operate with well knownautomatic temperature regulation.

Constant maintenance of a desired temperature in liquid metals throughthe incorporation of an inductive heating apparatus, and thesimultaneous prevention of the leaking in of air from the ambientatmosphere and of the leaking in of slag into container cavity 7 byvirtue of the use of the feed cavity and lower feed channel combination,permits normal treatment of liquid metals whose composition may vary,such as, for example, magnesium-treated iron for spherical graphiteiron. Normal casting can be carried out even after a fairly longinterruption of operations without losses in quality and without thenecessity of conducting a repeat treatment operation.

In addition, the siphon-type feed opening makes it possible to eliminatethe maintenance operation of slag removal from-the container 1altogether, because any slag introduced with the liquid metal into feedcavity 3 is automatically separated off over rim 19 of the feed opening6.

Because the liquid metal is already slag-free in the container 1, it ispossible to introduce alloying constituents or other elements into themolten metal, even if the additives have a lower specific gravity thanthe liquid metal.

Tests indicate that by virtue of the present apparatus, the life-span ofthe container lining, of the stopper seal 15, and of the stopper pouringopening 14 is considerably increased.

Because the maximal fill level of the liquid metal 18 in the container 1is limited by the height of the rim 19 of the feed opening 6, and thefill level in the feed cavity 3 of the feed container 2 can be visuallyobserved and controlled, there is no further need for the prior arttypes of feed control that was hitherto performed by means ofarocker-type mechanism.

Finally, it should be pointed out in addition to the above advantages,it has been found that the heat losses of the containers aresignificantly reduced. These heat losses must be replaced by means ofheat added by inductive heating. Thus, less heat must be added with thepresent invention.

A container in accordance with the present invention permits, by meansof coupling a vacuum pump to opening 20, the reduction of the gascontent of the liquid metal. As mentioned above, a gas can also beintroduced through the provided opening 20 so as to control theatmosphere in the container cavity 7.

Various modifications may be made to the illustrated embodiment Withinthe scope of this invention as set forth in the accompanying claims.

We claim:

1. Apparatus for the transfer of liquid metal, subject to slagformation, to casting molds comprising:

a closed container (1) having a cavity (7) therein for receiving liquidmetal and isolating the metal from ambient air, said container (1) beingformed with a pouring opening (14) located at a lower end portionthereof and stopper means (13) for selectively opening and closing saidpouring opening to selectively permit liquid metal to flow from thecontainer by gravity;

heating means (11) coupled to said container cavity (7) for heating theliquid metal therein;

a feed container (2) having a feed cavity (3) therein, said feedcontainer (2) being coupled to and in liquid communication with saidliquid container (1); said feed cavity extending at least as high as thedesired maximal liquid level in said container cavity (7) and said feedcontainer having an overflow rim (19);

a feed channel (4) coupled between the lower end portion of said feedcavity (3) and the lower end portion of said container cavity (7) andforming said liquid communication, such that liquid metal poured intosaid feed cavity (3) flows into said container cavity (7) through saidfeed channel (4) and liquid metal can be stored in the container freefrom contact with ambient air, and removed from the container by directflow through the pouring opening.

2. Apparatus according to claim 1 wherein said feed channel (4) isdownwardly inclined from said container cavity (7) to said feed cavity(3).

3. Apparatus according to claim 1 comprising a heating channel (12)coupling the lower end portion of said container cavity (7) to saidheating means (1 1).

4. Apparatus according to claim 3 wherein said heating channel (12) isdownwardly inclined from said container cavity (7) to said heating means(1 1).

5. Apparatus according to claim 4 wherein said feed channel (4) isdownwardly inclined from said container cavity (7) to said feed cavity(3).

6. Apparatus according to claim 5 wherein the angle of downwardinclination of said heating channel (12) is approximately equal to theangle of downward inclination of said feed channel (4).

7. Apparatus according to claim 1 wherein said heating means (12) andfeed container (2) are located alongside each other and on the same sideof said container (l).

8. Apparatus according to claim 6 wherein said heating means (12) andfeed container (2) are located alongside each other on n the sameside ofsaid container (l).

9. Apparatus according to claim 1 wherein said feed container (2)includes a wall having said rim (19) located at an overflow levelcorresponding to the maximum allowable liquid metal level (18) in saidcontainer (l such that when said liquid metal reaches said maximum level(18), further liquid metal poured into said feed container (2) willoverflow said wall, and slag will also overflow said wall.

10. Apparatus according to claim 1 wherein said stopper means comprisesa stopper bar (13) passing through a wall of said container (1), andfurther comprising sealing means coupled to said container for container(1) includes a valve type opening formed in a wall thereof forintroduction of additives or the like to said liquid metal.

13. Apparatus according to claim 2 wherein the bottom of said feedcavity is below the level of the bottom of said container cavity.

1. Apparatus for the transfer of liquid metal, subject to slagformation, to casting molds comprising: a closed container (1) having acavity (7) therein for receiving liquid metal and isolating the metalfrom ambient air, said container (1) being formed with a pouring opening(14) located at a lower end portion thereof and stopper means (13) forselectively opening and closing said pouring opening to selectivelypermit liquid metal to flow from the container by gravity; heating means(11) coupled to said container cavity (7) for heating the liquid metaltherein; a feed container (2) having a feed cavity (3) therein, saidfeeD container (2) being coupled to and in liquid communication withsaid liquid container (1); said feed cavity extending at least as highas the desired maximal liquid level in said container cavity (7) andsaid feed container having an overflow rim (19); a feed channel (4)coupled between the lower end portion of said feed cavity (3) and thelower end portion of said container cavity (7) and forming said liquidcommunication, such that liquid metal poured into said feed cavity (3)flows into said container cavity (7) through said feed channel (4) andliquid metal can be stored in the container free from contact withambient air, and removed from the container by direct flow through thepouring opening.
 2. Apparatus according to claim 1 wherein said feedchannel (4) is downwardly inclined from said container cavity (7) tosaid feed cavity (3).
 3. Apparatus according to claim 1 comprising aheating channel (12) coupling the lower end portion of said containercavity (7) to said heating means (11).
 4. Apparatus according to claim 3wherein said heating channel (12) is downwardly inclined from saidcontainer cavity (7) to said heating means (11).
 5. Apparatus accordingto claim 4 wherein said feed channel (4) is downwardly inclined fromsaid container cavity (7) to said feed cavity (3).
 6. Apparatusaccording to claim 5 wherein the angle of downward inclination of saidheating channel (12) is approximately equal to the angle of downwardinclination of said feed channel (4).
 7. Apparatus according to claim 1wherein said heating means (12) and feed container (2) are locatedalongside each other and on the same side of said container (1). 8.Apparatus according to claim 6 wherein said heating means (12) and feedcontainer (2) are located alongside each other on n the same side ofsaid container (1).
 9. Apparatus according to claim 1 wherein said feedcontainer (2) includes a wall having said rim (19) located at anoverflow level corresponding to the maximum allowable liquid metal level(18) in said container (1), such that when said liquid metal reachessaid maximum level (18), further liquid metal poured into said feedcontainer (2) will overflow said wall, and slag will also overflow saidwall.
 10. Apparatus according to claim 1 wherein said stopper meanscomprises a stopper bar (13) passing through a wall of said container(1), and further comprising sealing means coupled to said container forsealing the passage in said container wall through which said stopperbar (13) passes.
 11. Apparatus according to claim 1 wherein saidcontainer (1) includes a controllable opening means (20) for controlledintroduction or evacuation of gases from said container cavity (7). 12.Apparatus according to claim 1 wherein said container (1) includes avalve type opening formed in a wall thereof for introduction ofadditives or the like to said liquid metal.
 13. Apparatus according toclaim 2 wherein the bottom of said feed cavity is below the level of thebottom of said container cavity.